Akka/Scala example source code file (SingletonClusterSpec.scala)

This example Akka source code file (SingletonClusterSpec.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Akka and Scala source code examples by using tags.

All credit for the original source code belongs to akka.io; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Akka tags/keywords

a, akka, boolean, collection, concurrent, longrunningtest, multinodeclusterspec, multinodespec, singletonclustermultinodeconfig, singletonclusterspec, singletonclusterwithaccrualfailuredetectormultijvmnode1, singletonclusterwithfailuredetectorpuppetmultijvmnode1, singletonclusterwithfailuredetectorpuppetmultijvmnode2, test, testing, time

The SingletonClusterSpec.scala Akka example source code

/**
 * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
 */
package akka.cluster

import com.typesafe.config.ConfigFactory
import akka.remote.testkit.MultiNodeConfig
import akka.remote.testkit.MultiNodeSpec
import akka.testkit._
import scala.concurrent.duration._
import scala.collection.immutable

final case class SingletonClusterMultiNodeConfig(failureDetectorPuppet: Boolean) extends MultiNodeConfig {
  val first = role("first")
  val second = role("second")

  commonConfig(debugConfig(on = false).
    withFallback(ConfigFactory.parseString("""
      akka.cluster {
        auto-down-unreachable-after = 0s
        failure-detector.threshold = 4
      }
    """)).
    withFallback(MultiNodeClusterSpec.clusterConfig(failureDetectorPuppet)))

}

class SingletonClusterWithFailureDetectorPuppetMultiJvmNode1 extends SingletonClusterSpec(failureDetectorPuppet = true)
class SingletonClusterWithFailureDetectorPuppetMultiJvmNode2 extends SingletonClusterSpec(failureDetectorPuppet = true)

class SingletonClusterWithAccrualFailureDetectorMultiJvmNode1 extends SingletonClusterSpec(failureDetectorPuppet = false)
class SingletonClusterWithAccrualFailureDetectorMultiJvmNode2 extends SingletonClusterSpec(failureDetectorPuppet = false)

abstract class SingletonClusterSpec(multiNodeConfig: SingletonClusterMultiNodeConfig)
  extends MultiNodeSpec(multiNodeConfig)
  with MultiNodeClusterSpec {

  def this(failureDetectorPuppet: Boolean) = this(SingletonClusterMultiNodeConfig(failureDetectorPuppet))

  import multiNodeConfig._

  muteMarkingAsUnreachable()

  "A cluster of 2 nodes" must {

    "become singleton cluster when started with seed-nodes" taggedAs LongRunningTest in {
      runOn(first) {
        cluster.joinSeedNodes(Vector(first))
        awaitMembersUp(1)
        clusterView.isSingletonCluster should be(true)
      }

      enterBarrier("after-1")
    }

    "not be singleton cluster when joined with other node" taggedAs LongRunningTest in {
      awaitClusterUp(first, second)
      clusterView.isSingletonCluster should be(false)
      assertLeader(first, second)

      enterBarrier("after-2")
    }

    "become singleton cluster when one node is shutdown" taggedAs LongRunningTest in {
      runOn(first) {
        val secondAddress = address(second)
        testConductor.exit(second, 0).await

        markNodeAsUnavailable(secondAddress)

        awaitMembersUp(numberOfMembers = 1, canNotBePartOfMemberRing = Set(secondAddress), 30.seconds)
        clusterView.isSingletonCluster should be(true)
        awaitCond(clusterView.isLeader)
      }

      enterBarrier("after-3")
    }

    "leave and shutdown itself when singleton cluster" taggedAs LongRunningTest in {
      runOn(first) {
        cluster.leave(first)
        awaitCond(cluster.isTerminated, 5.seconds)
      }
      enterBarrier("after-4")
    }
  }
}